Previously, myriad devices have been developed for use in accessing and potentially visualizing sites within a body.
Many biomedical devices have mechanisms for manipulating the distal ends of the devices. Heretofore, the mechanisms for manipulating the distal ends of biomedical devices, by means at their proximal ends, have been based on the application of pulling force.
Single wire mechanisms for achieving distal manipulation of the device have been utilized. Such single wire devices can accomplish distal movement of a biomedical device only in a single direction relative to the central longitudinal axis. Thus, such single wire mechanisms have yielded movement only within one quadrant of a plane perpendicular to a plane corresponding to the longitudinal axis of the biomedical device. See, e.g., Bonello, et al., U.S. Pat. No. 4,734,093.
In order to accomplish effective distal movement of a device in more than one quadrant of a plane perpendicular to the longitudinal axis of a biomedical device, multiple wire mechanisms for achieving manipulation were employed. However, as with single wire mechanisms, multiple wire mechanisms achieve distal manipulation solely upon application of a pulling force. For example, two wires, each placed approximately 180.degree. opposite one another, and running from the proximal to the distal end of a device, were constructed into a device so that the distal ends of the wires were anchored at or near the distal end of the device. Thus, pulling one wire would move the distal end of the device in the direction that wire was located. In contrast, pulling the opposite wire would cause movement of the distal end of the device in the direction that wire was located. Thereby, movement of the distal end of such a device was accomplished in the plane extending between the two distal attachment points of the two wires. Consequent to the size of dual wire mechanisms for manipulation, the size of such a device was enlarged relative to devices that are not distally manipulable or that have single wire mechanisms for manipulation. An additional issue with multi-wire devices is the cost of producing such intricate devices. Due to their complexity, the devices tend to be very expensive.
Thus, there has been a need for a relatively compact, manipulable and cost-efficient mechanism for manipulating the distal end of a device.